Toothbrush



1935- I E. J. MGWHI RTER 2,016,153

TOOTHBRUSH Filed May 1, 1954 V Ear/JMc Whzfler Patented Oct. 1, 1935 UNITED STATES PATENT orries TOOTHBRUSH Earl J. McWhirter, Seattle, Wash.

Application May 1, 1934, Serial No. 723,334

5 Claims. (01. 306-28) My invention relates to brushes, though its principles are particularly applicable to toothbrushes, and especially to toothbrushes of the type which have a head separable from the handle, so that new heads may be put into use from time to time.

With many former toothbrushes of this general type heretofore proposed the head has been secured in place by devices such as a bolt extending through the handle, which has the disadvantage of being separable from the handle and head, and therefore likely to be lost or damaged, and the further disadvantage of increasing the cost of the brush. Other such devices, which do not have a separable member, nevertheless increase considerably the bulk and thickness of the head, that is,'the portion within the mouth, and provide pockets in such portion wherein dirt collects, and are objectionable on those scores. Accordingly it is an object of my invention to provide a brush having a separable head which is or may be of the same shape as ordinary toothbrushes, and which is no more bulky in any way, and which has not a separable member, but in which the head is secured to the handle by a device which is small and inconspicuous, and further, a brush having no pockets or crevices, especially in the head, for collection of dirt, etc.

It is a further object to lesson the cost of brushes having removable heads.

It is a further object to devise a toothbrush of this general character which may have a curved handle, if desired.

It is a further object to provide a toothbush of this general character wherein the head may be securely locked to the handle, and to provide interconnecting and locking means so arranged and formed that there are no joints or apertures in the brush which will admit water, toothpowder or paste, and which is therefore sanitary throughout, and further, one which is provided with locking means which are so located and operated that they will be engaged by one or more of the fingers of a hand naturally grasping the brush, and pressed in such a direction by such finger as to'hold it in locked position.

Another object is to arrange the interconnecting means and the locking means in such a way that if the interconnecting means are improperly assembled the locking means will not operate, thus insuring proper assembly.

Other objects, and more especially such as relate to the purely mechanical details of the brush, will be understood as this specification progresses.

My invention comprises the novel brush and the novel combination and arrangement of the parts thereof, as shown in the accompanying drawing, and as will be described in this specification and more particularly defined by the claims terminating the same.

In the accompanying drawing I have shown my 1 invention embodied in a form which is now preferred by me, it being understood, however, that the mechanical details are susceptible of variations in manners which will be pointed out and in other ways which will occur to a skilled mechanic.

Figure 1 is a plan view of the brush, looking toward the bristles.

Figure 2 is an enlarged plan view of the adjoining portions of the head and handle, parts being broken away, and the parts being shown in locked position.

Figure 3 is a side elevation, the handle being broken away to show the manner of locking the head to the handle.

Figure 4. is a vertical section through they adjoining portions of the head and handle, showing parts in the unlocked position.

Figure 5 is a transverse section through the handle on the line 55 of Figure 4.

The head, generally indicated by the numeral I, may be formed, with exceptions that will be noted, in any suitable fashion and of any suitable material. It consists of a base it formed with a neck l l which may all be of bakelite or celluloid, in which head are set the bristles l2. The shape of this head and the shape and pattern of the bristles may be varied as the trade may demand.

Projecting from the end of the neck I i is a stem 2. Preferably this is of metal, and it is shown as formed upon a collar 20 which is of the same curvature and shape as the end of the neck H, which it joins by smooth curves. To secure the stem to the head any suitable arrangement may be provided, as, for instance, by providing a second stem 2! upon the collar 20 which is threaded within the neck l l, or which is embedded therein during the manufacture of the head. The collar 2b is preferably formed with a sharp shoulder at 22.

The handle 3 may be made of any suitable material, bakelite, celluloid, or metal, and may have any desired curvature or shape. Within one end it is socketed, as indicated at 32, to receive the stem 2. The exterior surface of the handle merges smoothly into the surfaces of the collar 25 and neck H, and its end fits closely the shoulder 22. In order to prevent relative rotation of the handle and head, and for another purpose which will appear hereafter, I prefer that there be a slight projection 3!! beyond the end of the handle which abuts the shoulder 22, and that the collar 2t be recessed, as is best seen in Figure 3, for the reception of this projection 3|, thus providing in terengaging means to prevent relative rotation of the handle and head. Only one such means is provided, and consequently the brush and handle must be in proper relative positions before the projection 31 will engage within its corresponding recess. This is desirable in order to bring the curvature of the handle, if the handle has curvature, in proper position with relation to the bristles, and in order to obtain proper engagement of the locking means to be described. 7

Intersecting the socket 32 is an aperture punched in the handle 3, within which is received a pin 4. The pin may be formed with a head 40 which closes the aperture at one side, and adjacent its other end may be formed with a flange 4i and a substantially rectangular projection 42, and a locking dog 5, projecting from adisk 50, is supported from the pin 4. The disk, as may be seen in Figures 2 and 4, is provided with a substantially recangular hole fitting the projection 42 on the pin, and thus the locking dog 5 may be rotated by rotating the pin 4. To limit the amount of rotation, a stop lug 5i may be formed projecting from the periphery of the disk at, and the aperture is suitably recessed, as seen in Figure 4, to permit substantially 90 rotation of the disk. To hold the several parts together, to provide convenient means for rotating the pin and disk, and to close the aperture 7 through the handle at the side opposite the head 46 of the pin,-I provide a plate 6 which lies flat against the face of the handle, and which may be provided with a substantially rectangular hole fitting over the portion 52 of the pin, which is then swaged over to hold the plate 6 in place. The plate 6 is in effect a small lever, and by turning it the locking dog 5 is turned, and this rotation is permitted through about 90.

The stem 2 is provided with a transverse arcuate slot 25 which, when the parts are properly assembled, is located within the path of movement of the rotative dog 5. The curvature of the slot is then identical with the dogs path. The parts are so positioned in Figure 2, and the dog 5 has been engaged within the slot 25, thus locking the stem 2 and its head! securely to the handle. In Figure 4 the dog is shown swung aside in the unlocked position, and the stem may now be freely withdrawn from the socket 32.

If it be attempted to assemble the head upon the handle in improper relationship thereto the projection 3|, riding upontheshoulder 22, will prevent entrance of the stem 2 within its socket to an extent sufiicient'to bring the slot 25 into registry with the path of movement of the locking dog 5, and thus parts cannot be locked together unless they are properly assembled, and when properly assembled and locked, rotation is prevented and parts are held so closely adjacent that there is no aperture for the entrance of water,

paste or powder. The dog 5 might be somewhat wedge shaped, if that were found necessary, in order to draw the shoulder 22 more firmly against the end of the handle. This, however, will be found an unnecessary precaution with reasonably accurate manufacture of the parts.

The locked position of the plate 6 is shown in Figures 1 and 2, and it will be observed that when a person grasps the handle in his right hand his thumb will naturally rest upon the plate 6 in such manner as to tend to press it downward, as seen in these two figures, that is, further toward the locking position, and thus by the natural grasp of the hand this-locking device is held in locked position during use.

- The handle 3 might well be made, in whole or in part, of material other than metal, for the strain upon it is not great. The aperture for the locking device can be punched or molded in the handle. The same principles of construction can be incorporated in brushes of various types, one

of the distinguishing features being the interengagement of parts of the head and handle, and the locking thereof by means which are incorporated in one of the interengaged parts.

What I claim as my invention is: 5 1. In combination with a brush head having a stem, a handle socketed to receive the stem,

the handle having a transverse aperture intersecting the socket, a headed pin rotatively received in said aperture, the head closing the aper- 10 ture at one side, a disk received in the aperture opposite the head of the pin, the pin and disk having non-circular interengaging means, a locking dog extending from the disk into the socket, a stop lug formed on the periphery of the disk, the aperture being recessed for the reception of such lug, to permit substantially 90 rotation thereof, the stem having an arcuate slot disposed, when the parts are assembled, to receive the looking dog, and an operating lever secured upon the pin, and closing the aperture at the side opposite the head of the pin.

2. In combination with a toothbrush head having a stern, a handle socketed to receive the stem,

the handle having a transverse aperture intersecting the socket, a headed pin rotatively received in said aperture, the head closing the aperture at one side, an operating lever secured upon the pin opposite the head of the pin, and closing the opposite side of the aperture, a locking dog rotatable with the pin and extending into the socket, and the stem having an arcuate slot disposed, when the parts are assembled, to receive the dog.

3. In combination with a toothbrush head having a stem, a handle socketed to receive the stem, the handle having a transverse aperture intersecting the socket, a pin rotatively receivedin the aperture, a disk mounted upon the pin to rotate therewith and disposed at one side of the 4?} socket, a locking dog extending from the disk into the socket, the stern having an arcuate slot disposed, when the parts are assembled, to receive the locking dog, and an external operating lever secured on the pin.

l. In combination with a toothbrush head having a stem, a handle socketed to receive the stem, the handle having a transverse aperture intersecting the socket, a pin rotatively received in the aperture and having one end of non-circular form, a disk having a correspondingly non-circular hole whereby it is received on the pin to rotate therewith, a locking dog extending from the disk into the socket, the stem having an arcuate slot disposed, when the parts are assembled, to receive the locking dog, and an external operating lever secured upon the pin, outside of the disk, thereby to retain the disk upon the pin.

5. In combination with a toothbrush head having a stern, a handle socketed to receive the stem, thehandle having a transverse aperture intersecting the socket, a pin rotatively received in the aperture, a disk received in the aperture at one end of the pin, the pin and disk having noncircular interengaging means, a locking dog ro- 6 tatable with the pin and extending into the socket, the stem having an arcuate slot disposed, when the parts are assembled, to receive the locking dog, a stop lug formed on the periphery of the disk, the aperture being recessed for the reception of such lug, to permit substantially rotation thereof, and an external operating lever secured upon the pin and closing its side of the aperture.

EARL J. MCWHIRTER. '15 

